CHART OF TODAY: Apple's Surprisingly Steady iTunes Growth

Apple’s iTunes business exceeded $4 billion revenue last quarter. Horace Dediu broke down where all the sales are coming from on his site, Asymco. As you can see, it’s mostly a mix of content and app sales.

The interesting thing, Dediu notes, is that growth has been steady at 29% each quarter. This is happening despite the competitive environment where Netflix, Spotify, Google, and Amazon are all trying to chip away at Apple’s iTunes franchise in one way or another.